4 files changed, 59 insertions, 14 deletions

diff --git a/source/blender/functions/FN_attributes_ref.hh b/source/blender/functions/FN_attributes_ref.hh
index ed14676731e..c694f11b7a7 100644
--- a/source/blender/functions/FN_attributes_ref.hh
+++ b/source/blender/functions/FN_attributes_ref.hh
@@ -50,12 +50,12 @@ class AttributesInfoBuilder : NonCopyable, NonMovable {
   AttributesInfoBuilder() = default;
   ~AttributesInfoBuilder();
 
-  template<typename T> void add(StringRef name, const T &default_value)
+  template<typename T> bool add(StringRef name, const T &default_value)
   {
-    this->add(name, CPPType::get<T>(), (const void *)&default_value);
+    return this->add(name, CPPType::get<T>(), (const void *)&default_value);
   }
 
-  void add(StringRef name, const CPPType &type, const void *default_value = nullptr);
+  bool add(StringRef name, const CPPType &type, const void *default_value = nullptr);
 };
 
 /**
diff --git a/source/blender/functions/FN_cpp_type.hh b/source/blender/functions/FN_cpp_type.hh
index 594890e353a..531a9073784 100644
--- a/source/blender/functions/FN_cpp_type.hh
+++ b/source/blender/functions/FN_cpp_type.hh
@@ -371,7 +371,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void copy_to_initialized_n(const void *src, void *dst, int64_t n) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(n == 0 || src != dst);
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(dst));
 
@@ -380,7 +380,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void copy_to_initialized_indices(const void *src, void *dst, IndexMask mask) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(mask.size() == 0 || src != dst);
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(dst));
 
@@ -406,7 +406,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void copy_to_uninitialized_n(const void *src, void *dst, int64_t n) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(n == 0 || src != dst);
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(dst));
 
@@ -415,7 +415,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void copy_to_uninitialized_indices(const void *src, void *dst, IndexMask mask) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(mask.size() == 0 || src != dst);
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(dst));
 
@@ -441,7 +441,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void relocate_to_initialized_n(void *src, void *dst, int64_t n) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(n == 0 || src != dst);
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(dst));
 
@@ -450,7 +450,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void relocate_to_initialized_indices(void *src, void *dst, IndexMask mask) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(mask.size() == 0 || src != dst);
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(dst));
 
@@ -476,7 +476,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void relocate_to_uninitialized_n(void *src, void *dst, int64_t n) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(n == 0 || src != dst);
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(n == 0 || this->pointer_can_point_to_instance(dst));
 
@@ -485,7 +485,7 @@ class CPPType : NonCopyable, NonMovable {
 
   void relocate_to_uninitialized_indices(void *src, void *dst, IndexMask mask) const
   {
-    BLI_assert(src != dst);
+    BLI_assert(mask.size() == 0 || src != dst);
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(src));
     BLI_assert(mask.size() == 0 || this->pointer_can_point_to_instance(dst));
 
diff --git a/source/blender/functions/FN_spans.hh b/source/blender/functions/FN_spans.hh
index c50c92cd16d..a81f3ea3633 100644
--- a/source/blender/functions/FN_spans.hh
+++ b/source/blender/functions/FN_spans.hh
@@ -209,6 +209,20 @@ template<typename T> struct VSpanBase {
     return false;
   }
 
+  bool is_full_array() const
+  {
+    switch (category_) {
+      case VSpanCategory::Single:
+        return virtual_size_ == 1;
+      case VSpanCategory::FullArray:
+        return true;
+      case VSpanCategory::FullPointerArray:
+        return false;
+    }
+    BLI_assert(false);
+    return false;
+  }
+
   bool is_empty() const
   {
     return this->virtual_size_ == 0;
@@ -285,6 +299,22 @@ template<typename T> class VSpan : public VSpanBase<T> {
     BLI_assert(false);
     return *this->data_.single.data;
   }
+
+  const T &as_single_element() const
+  {
+    BLI_assert(this->is_single_element());
+    return (*this)[0];
+  }
+
+  Span<T> as_full_array() const
+  {
+    BLI_assert(this->is_full_array());
+    if (this->virtual_size_ == 0) {
+      return Span<T>();
+    }
+    const T *data = &(*this)[0];
+    return Span<T>(data, this->virtual_size_);
+  }
 };
 
 /**
@@ -395,6 +425,16 @@ class GVSpan : public VSpanBase<void> {
     return (*this)[0];
   }
 
+  GSpan as_full_array() const
+  {
+    BLI_assert(this->is_full_array());
+    if (this->virtual_size_ == 0) {
+      return GSpan(*this->type_);
+    }
+    const void *data = (*this)[0];
+    return GSpan(*this->type_, data, this->virtual_size_);
+  }
+
   void materialize_to_uninitialized(void *dst) const
   {
     this->materialize_to_uninitialized(IndexRange(virtual_size_), dst);
diff --git a/source/blender/functions/intern/attributes_ref.cc b/source/blender/functions/intern/attributes_ref.cc
index 7bfcc69671a..4686e217911 100644
--- a/source/blender/functions/intern/attributes_ref.cc
+++ b/source/blender/functions/intern/attributes_ref.cc
@@ -25,7 +25,7 @@ AttributesInfoBuilder::~AttributesInfoBuilder()
   }
 }
 
-void AttributesInfoBuilder::add(StringRef name, const CPPType &type, const void *default_value)
+bool AttributesInfoBuilder::add(StringRef name, const CPPType &type, const void *default_value)
 {
   if (names_.add_as(name)) {
     types_.append(&type);
@@ -36,10 +36,15 @@ void AttributesInfoBuilder::add(StringRef name, const CPPType &type, const void
     void *dst = allocator_.allocate(type.size(), type.alignment());
     type.copy_to_uninitialized(default_value, dst);
     defaults_.append(dst);
+    return true;
   }
   else {
-    /* The same name can be added more than once as long as the type is always the same. */
-    BLI_assert(types_[names_.index_of_as(name)] == &type);
+    const CPPType &stored_type = *types_[names_.index_of_as(name)];
+    if (stored_type != type) {
+      std::cout << "Warning: Tried to add an attribute twice with different types (" << name
+                << ": " << stored_type.name() << ", " << type.name() << ").\n";
+    }
+    return false;
   }
 }